The present invention is directed to a mouthguard fabricated from a polymer blend comprising ethylene vinyl acetate and thermoplastic polyurethane, and a method of fabricating a mouthguard from such a polymer blend.
Conventionally, in a contact sport such as football, basketball, hockey or the like, an accident, for example, fracture of jaw bone, a laceration of soft tissue of the oral cavity, or the like, has frequently happened. Accordingly, in order to prevent such an accident, it is desired to put a mouthpiece in a mouth.
A number of mouthguards currently exist in the art for protecting the teeth and for reducing the chance of shock, concussions and other injuries as a result of high impact collisions and blows during athletic competition. Mouthguards generally are characterized as being nonpersonalized, universal and stock model type; xe2x80x9cboil and bitexe2x80x9d; and custom thermoformed to have upper jaw and teeth direct contact. Additionally, mouthguards may be tethered or untethered. Tethered mouthguards are usually connected to a fastening point, such as a helmet or face guard, to prevent the chance of the mouthguard from being lost as well as to prevent swallowing of the mouthguard or choking on the mouthguard by the user.
Failure to use a mouthguard or the use of an improperly fitted mouthguard when impacts, collisions or blows occur to the jaw structure of an athlete have been found to be responsible for athletes"" susceptibility to headaches, presence of earaches, ringing in the ears, clogged ears, vertigo, concussions and dizziness. The cause of these types of health problems and injuries are generally not visible by inspection of the mouth or jaw, but more particularly relate to the temporomandibular joint (TMJ) and surrounding tissues where the lower jaw is connected to the skull in the proximity where the auriculo-temporalis nerves and supra-temporal arteries pass from the neck nerves into the skull to the brain.
Most mouthguards in the past have been made from ethylene vinyl acetate (EVA). The material has a softening point approximating the temperature of boiling water which will permit the mouthguard to be placed in boiling water and custom fit to the wearer""s mouth. However, the EVA material, although the best known to date, is not ideal for absorption, attenuation, and dissipation of shock forces exerted on the EVA mouthguard during athletic activity. Furthermore, the EVA material is subject to deformation and break down with continued use and chewing thereon by the wearer. There is a need, therefore, for a mouthguard having a higher ability for the absorption, attenuation and dissipation of shock forces as compared with conventional, EVA mouthguards.
This and other objects of the invention are achieved by a mouthguard, fitted to the molar and incisor teeth and gums of a human user. Such a mouthguard comprises a blend of ethylene vinyl acetate (EVA) and thermoplastic urethane (TPU), especially a blend, wherein the EVA is present in the range of about 5 to about 95% by weight and the balance is TPU.
In some aspects, the mouthguard is fitted at a temperature in excess of 100xc2x0 C. with reference to a model of the human user""s teeth. In other aspects, the mouthguard is fitted at a temperature of less than 100xc2x0 C. with direct reference to the human user""s teeth.
In these latter embodiments, the mouthguard comprises a generally U-shaped body with an upper surface and a lower surface, the upper surface having a channel fitted to the upper molar and incisor teeth and gums of the user. A first arm portion of the body corresponds to the right upper molars and gums of the user and a second arm portion of the body corresponds to the left upper molars and gums of the user. A base portion joining the first and second arm portions corresponds to the incisors and gums of the user. In some of these embodiments, a first cushion pad is arranged in the first arm portion and a second cushion pad is arranged in the second arm portion.